A major challenge confronting military units and hazardous materials response teams involves the accurate and rapid identification of organic or inorganic chemicals outside the typical laboratory environment and under potentially dangerous conditions. Extreme care is required when analyzing unknown chemicals because of the possible instability of samples. Many chemicals can be sensitive to shock, heat, or light and could react violently including deflagration or explosion. In many cases, determining the nature of the unknown materials, whether biological (microorganisms) or chemical, is important and will dictate the handling, cleanup, disposal, and resolution of military or civilian issues.
Addressing the need for rapid and accurate analysis of samples that are suspected to be dangerous has been difficult for most current commercial analytical instruments available to military personnel and law enforcement field agents, especially given the fact that analysis may prove lethal if handled incorrectly. Many previous efforts to provide remote detection or identification have met with limited success. Radar-style imaging methods as described in U.S. Pat. Nos. 6,243,036, 6,359,582, and 7,205,926, and U.S. Patent Application Number 2005/0099330 demonstrated object detection at a distance; however, those inventions could not identify chemicals and chemical compounds. Raman and infrared (IR) spectroscopy methods as described in U.S. Pat. Nos. 5,112,127 and 7,301,148 demonstrated chemical compound identification: however, they were limited by sample preparation, strong IR absorbers like water, CO2, and glass (silica), and they required close or direct contact with the sample. U.S. Pat. Nos. 5,112,127, 6,243,036, 6,359,582, 7,205,926, and 7,301,148, and U.S. Patent Application Number 2005/0099330, are incorporated herein in their entireties by reference for all purposes.
Thus, what is needed is a method and apparatus for remotely detecting, locating, and identifying chemicals and chemical compounds at a safe standoff distance that does not require sample preparation and is not limited by strong IR absorbers or containers.